Question

我对编程很新，而且这个程序运行，但是当我能够输入击球记录时，控制台出现Windows错误＆＃34; .exe已停止工作......＆＃34 ;.这从未发生过，作为一名新程序员，我认为这很可怕。

#include <iostream>
using namespace std;

//Prototype to keep console from closing.
class KeepRunning {
  public:
    ~KeepRunning() {
      system("pause");}};

//Define batting values
#define H  1
#define h  1
#define O  1
#define o  1
#define W  0
#define w  0
#define S  0
#define s  0
#define P  0
#define p  0

int main ()
{
  KeepRunning kr;

  int player;                 //Assign player number
  double sum;                 //Assign variable for sum of H, h and O, o
  double sumHits;             //Assign variable for sum of only H and h
  double average;             //Assign variable for average of H and O
  char size[100];             //Allows compiler to view user input as array
  int b;                      //Assign variable for integer size
  int letters = 0;            //Assing value of 0 to allow compiler to count

  cout << "\t\t\tBatting Average Calculator\t\t";

  cout << "\n\nEnter the player's number: ";
  cin >> player;

  cout << "Enter the player's batting record: ";
  cin >> size;

  bool invalid = false;
  while(!invalid)
  {
    invalid = true;
    if ((size[b] == 'H') || (size[b] == 'h')
        || (size[b] == 'O') || (size[b] == 'o')
        || (size[b] == 'W') || (size[b] == 'w')
        || (size[b] == 'S') || (size[b] == 's')
        || (size[b] == 'P') || (size[b] == 'p'))
    { 
      continue; 
    } 
    else {
     cout << "\nAcceptable batting record codes are: 'H','O','W','S','P'. 
            Please try again.\n"; 
     invalid = false;
    }
  }

  //Summate H, h, O, o
  sum = H + h + O + o;

  //Summate 
  sumHits = H + h;

  //Calculate batting average
  average = sumHits/sum;

  cout << "\nPlayer " << player << "'s batting record: " << size << endl;
  cout << "Player " << player << "'s batting average: " << average << endl;

  std::cout << "Press ENTER to continue...";
  std::cin.ignore( std::numeric_limits<std::streamsize>::max(), '\n' );         
  return 0;
}

好的，所以我已经做了一些改变，感谢yall。但是，我遇到了新问题。首先，当我运行程序并写一个有效的输入，即＆＃34; HOWHHHOOWHSPP＆＃34;时，没有任何反应。控制台只是保持打开状态，显示提示和输入。第二，当我写一个无效的输入时，即＆＃34; HOWQQQTTSHH＆＃34;或者不包括特定字母集的任何内容，控制台立即关闭而不是显示我的错误消息。如何让控制台不仅保持打开状态，而且重定向程序以重新开始输入任何无效的输入？

这是新代码：

#include <iostream>
using namespace std;

//Prototype to keep console from closing.
class KeepRunning {
  public:
    ~KeepRunning() {
      cin.get();}};

//Define batting values
#define H  1
#define h  1
#define O  1
#define o  1
#define W  0
#define w  0
#define S  0
#define s  0
#define P  0
#define p  0

int main ()
{
    KeepRunning kr;

    int player;                 //Assign player number
    double sum;                 //Assign variable for sum of H, h and O, o
    double sumHits;             //Assign variable for sum of only H and h
    double average;             //Assign variable for average of H and O
    char size[100];             //Allows compiler to view user input as array
    int b=0;                    //Assign variable for integer size
    int letters = 0;            //Assing value of 0 to allow compiler to count

    cout << "\t\t\tBatting Average Calculator\t\t";

    cout << "\n\nEnter the player's number: ";
    cin >> player;

    cout << "Enter the player's batting record: ";
    cin >> size;

    bool invalid = false;
    while (!invalid && size[b] != '\0')
    {
     if (size[b] != 'H' && size[b] != 'h' &&
         size[b] != 'O' && size[b] != 'o' &&
         size[b] != 'W' && size[b] != 'w' &&
         size[b] != 'S' && size[b] != 's' &&
         size[b] != 'P' && size[b] != 'p') 
       {
        invalid = true;
       }
      else {
       invalid = false;
       }
    }                   
    //Summate H, h, O, o
    sum = H + h + O + o;

    //Summate 
    sumHits = H + h;

    //Calculate batting average
    average = sumHits/sum;

    cout << "\nPlayer " << player << "'s batting record: " << size << endl;
    cout << "Player " << player << "'s batting average: " << average << endl;

    return 0;
}

Answer 1

在行

cout << "Enter the player's batting record: ";
cin >> size;

我认为您应该将输入发送到b，而不是size。在您的代码中b未初始化，因此它包含垃圾值。当您使用b作为size的索引时，索引无效，这会导致程序崩溃。

Answer 2

看起来问题是你在为数组赋值之前尝试使用变量b作为数组的索引。我想你想要的是一个循环来检查用户输入的所有字符，所以像这样：

int b = 0;

while (!invalid && size[b] != '\0') {
    //stuff in your existing loop
}

'\ 0'会自动添加到用户输入的末尾，并向循环指示已读取用户输入的所有字符。

作为旁注，最好重构循环以检查您检查的输入是否无效，如果是，则将invalid设置为true。这里没有理由继续使用。这样的事情会更好：

if (size[b] != 'H' && size[b] != 'h' &&
    size[b] != 'O' && size[b] != 'o' &&
    ....etc.) {
    invalid = true;
}

一旦遇到无效字符，循环就会结束。

.exe已停止工作

2 个答案: